Don't know how much 4000Bs usually go for... They've gone as low as $200 up to $350 used on Ebay. New, seems like $450 is common.
Either way, wouldn't be my pick for a mic... I mean it'll do, but considering others out there for the price... Then again, I say that for every current AKG mic, so admitably, I'm probably a little bias. I don't own any current AKG mics nor any old AKG mics right now. I had a pair of C451s, but sold them quite a time ago because they needed some repair (one was dull as hell and the other was noisey as hell... I KNEW I shouldn't have! SPA would be modding them with 0.9 micron skins right now if I hadn't! DAMN ME! Harvey warned me too!!!
Oh well, will just have to pickup a pair of bodies sometime this year and pickup a pair of omni caps as I find them. Either that or pickup a pair of Milab VM44 Omnis, Pearl TL66Ks, or a pair of the Josephson mics! Then, eventually have SPA mod them!
Oh, by the way, it should be noted, if
the RCA 77 on Letterman isn't a prop mic, then it's probably some-sort of small condenser inside an RCA 77 housing!